[PATCH] v9fs: new multiplexer implementation
New multiplexer implementation. Decreases the number of kernel threads
required. Better handling when the user process receives a signal.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/9p/trans_sock.c b/fs/9p/trans_sock.c
index 6a9a75d..9ef404c 100644
--- a/fs/9p/trans_sock.c
+++ b/fs/9p/trans_sock.c
@@ -3,6 +3,7 @@
*
* Socket Transport Layer
*
+ * Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net>
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
* Copyright (C) 1995, 1996 by Olaf Kirch <okir@monad.swb.de>
@@ -36,6 +37,7 @@
#include <asm/uaccess.h>
#include <linux/inet.h>
#include <linux/idr.h>
+#include <linux/file.h>
#include "debug.h"
#include "v9fs.h"
@@ -45,6 +47,7 @@
struct v9fs_trans_sock {
struct socket *s;
+ struct file *filp;
};
/**
@@ -57,41 +60,26 @@
static int v9fs_sock_recv(struct v9fs_transport *trans, void *v, int len)
{
- struct msghdr msg;
- struct kvec iov;
- int result;
- mm_segment_t oldfs;
- struct v9fs_trans_sock *ts = trans ? trans->priv : NULL;
+ int ret;
+ struct v9fs_trans_sock *ts;
- if (trans->status == Disconnected)
+ if (!trans || trans->status == Disconnected) {
+ dprintk(DEBUG_ERROR, "disconnected ...\n");
return -EREMOTEIO;
+ }
- result = -EINVAL;
+ ts = trans->priv;
- oldfs = get_fs();
- set_fs(get_ds());
+ if (!(ts->filp->f_flags & O_NONBLOCK))
+ dprintk(DEBUG_ERROR, "blocking read ...\n");
- iov.iov_base = v;
- iov.iov_len = len;
- msg.msg_name = NULL;
- msg.msg_namelen = 0;
- msg.msg_iovlen = 1;
- msg.msg_control = NULL;
- msg.msg_controllen = 0;
- msg.msg_namelen = 0;
- msg.msg_flags = MSG_NOSIGNAL;
-
- result = kernel_recvmsg(ts->s, &msg, &iov, 1, len, 0);
-
- dprintk(DEBUG_TRANS, "socket state %d\n", ts->s->state);
- set_fs(oldfs);
-
- if (result <= 0) {
- if (result != -ERESTARTSYS)
+ ret = kernel_read(ts->filp, ts->filp->f_pos, v, len);
+ if (ret <= 0) {
+ if (ret != -ERESTARTSYS && ret != -EAGAIN)
trans->status = Disconnected;
}
- return result;
+ return ret;
}
/**
@@ -104,40 +92,73 @@
static int v9fs_sock_send(struct v9fs_transport *trans, void *v, int len)
{
- struct kvec iov;
- struct msghdr msg;
- int result = -1;
+ int ret;
mm_segment_t oldfs;
- struct v9fs_trans_sock *ts = trans ? trans->priv : NULL;
+ struct v9fs_trans_sock *ts;
- dprintk(DEBUG_TRANS, "Sending packet size %d (%x)\n", len, len);
+ if (!trans || trans->status == Disconnected) {
+ dprintk(DEBUG_ERROR, "disconnected ...\n");
+ return -EREMOTEIO;
+ }
+
+ ts = trans->priv;
+ if (!ts) {
+ dprintk(DEBUG_ERROR, "no transport ...\n");
+ return -EREMOTEIO;
+ }
+
+ if (!(ts->filp->f_flags & O_NONBLOCK))
+ dprintk(DEBUG_ERROR, "blocking write ...\n");
+
dump_data(v, len);
-
- down(&trans->writelock);
-
oldfs = get_fs();
set_fs(get_ds());
- iov.iov_base = v;
- iov.iov_len = len;
- msg.msg_name = NULL;
- msg.msg_namelen = 0;
- msg.msg_iovlen = 1;
- msg.msg_control = NULL;
- msg.msg_controllen = 0;
- msg.msg_namelen = 0;
- msg.msg_flags = MSG_NOSIGNAL;
- result = kernel_sendmsg(ts->s, &msg, &iov, 1, len);
+ ret = vfs_write(ts->filp, (void __user *)v, len, &ts->filp->f_pos);
set_fs(oldfs);
- if (result < 0) {
- if (result != -ERESTARTSYS)
+ if (ret < 0) {
+ if (ret != -ERESTARTSYS)
trans->status = Disconnected;
}
- up(&trans->writelock);
- return result;
+ return ret;
}
+static unsigned int v9fs_sock_poll(struct v9fs_transport *trans,
+ struct poll_table_struct *pt) {
+
+ int ret;
+ struct v9fs_trans_sock *ts;
+ mm_segment_t oldfs;
+
+ if (!trans) {
+ dprintk(DEBUG_ERROR, "no transport\n");
+ return -EIO;
+ }
+
+ ts = trans->priv;
+ if (trans->status != Connected || !ts) {
+ dprintk(DEBUG_ERROR, "transport disconnected: %d\n", trans->status);
+ return -EIO;
+ }
+
+ oldfs = get_fs();
+ set_fs(get_ds());
+
+ if (!ts->filp->f_op || !ts->filp->f_op->poll) {
+ dprintk(DEBUG_ERROR, "no poll operation\n");
+ ret = -EIO;
+ goto end;
+ }
+
+ ret = ts->filp->f_op->poll(ts->filp, pt);
+
+end:
+ set_fs(oldfs);
+ return ret;
+}
+
+
/**
* v9fs_tcp_init - initialize TCP socket
* @v9ses: session information
@@ -154,9 +175,9 @@
int rc = 0;
struct v9fs_trans_sock *ts = NULL;
struct v9fs_transport *trans = v9ses->transport;
+ int fd;
- sema_init(&trans->writelock, 1);
- sema_init(&trans->readlock, 1);
+ trans->status = Disconnected;
ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
@@ -165,6 +186,7 @@
trans->priv = ts;
ts->s = NULL;
+ ts->filp = NULL;
if (!addr)
return -EINVAL;
@@ -185,7 +207,18 @@
return rc;
}
csocket->sk->sk_allocation = GFP_NOIO;
+
+ fd = sock_map_fd(csocket);
+ if (fd < 0) {
+ sock_release(csocket);
+ kfree(ts);
+ trans->priv = NULL;
+ return fd;
+ }
+
ts->s = csocket;
+ ts->filp = fget(fd);
+ ts->filp->f_flags |= O_NONBLOCK;
trans->status = Connected;
return 0;
@@ -203,7 +236,7 @@
v9fs_unix_init(struct v9fs_session_info *v9ses, const char *dev_name,
char *data)
{
- int rc;
+ int rc, fd;
struct socket *csocket;
struct sockaddr_un sun_server;
struct v9fs_transport *trans;
@@ -213,6 +246,8 @@
csocket = NULL;
trans = v9ses->transport;
+ trans->status = Disconnected;
+
if (strlen(dev_name) > UNIX_PATH_MAX) {
eprintk(KERN_ERR, "v9fs_trans_unix: address too long: %s\n",
dev_name);
@@ -225,9 +260,7 @@
trans->priv = ts;
ts->s = NULL;
-
- sema_init(&trans->writelock, 1);
- sema_init(&trans->readlock, 1);
+ ts->filp = NULL;
sun_server.sun_family = PF_UNIX;
strcpy(sun_server.sun_path, dev_name);
@@ -241,7 +274,18 @@
return rc;
}
csocket->sk->sk_allocation = GFP_NOIO;
+
+ fd = sock_map_fd(csocket);
+ if (fd < 0) {
+ sock_release(csocket);
+ kfree(ts);
+ trans->priv = NULL;
+ return fd;
+ }
+
ts->s = csocket;
+ ts->filp = fget(fd);
+ ts->filp->f_flags |= O_NONBLOCK;
trans->status = Connected;
return 0;
@@ -262,12 +306,11 @@
ts = trans->priv;
- if ((ts) && (ts->s)) {
- dprintk(DEBUG_TRANS, "closing the socket %p\n", ts->s);
- sock_release(ts->s);
+ if ((ts) && (ts->filp)) {
+ fput(ts->filp);
+ ts->filp = NULL;
ts->s = NULL;
trans->status = Disconnected;
- dprintk(DEBUG_TRANS, "socket closed\n");
}
kfree(ts);
@@ -280,6 +323,7 @@
.write = v9fs_sock_send,
.read = v9fs_sock_recv,
.close = v9fs_sock_close,
+ .poll = v9fs_sock_poll,
};
struct v9fs_transport v9fs_trans_unix = {
@@ -287,4 +331,5 @@
.write = v9fs_sock_send,
.read = v9fs_sock_recv,
.close = v9fs_sock_close,
+ .poll = v9fs_sock_poll,
};